Problems

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Total results29,423 problems

Sorting by moving pairs
Medium6
Combinatorics, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Game
Medium6
Game theory, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sorting the Barbells
Medium6
Greedy, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Word Ladder
Medium6
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Contest Problem Assignment
Medium6
Dynamic programming, Bit manipulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Cycling
Medium6
Shortest path, Two pointers+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Algebra
Medium6
Math, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Reverse Engineering
Medium6
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Taunt Bot
Medium6
Simulation, String+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
If only I could think Linearly...
Medium6
Matrix, Brute force
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Who needs 8 queens when you can have N?
Medium6
Backtracking, Recursion+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Jill's Tour Paths
Medium6
Backtracking, DFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bounded Cellular Automata
Medium6
Simulation, Hash map+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Unscrambling Images
Medium6
Tree, Recursion+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Prime Caves
Medium6
Dynamic programming, Number theory+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Boggle
Medium6
Trie, DFS+1
No attempts yet
Time limit
10s
Memory limit
512 MB
Judgeable
Powerbase Format
Medium6
Backtracking, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Superstitious Helicopter Pilots
Medium6
Dynamic programming, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Urns
Medium6
Simulation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Steve Jobsoong
Medium6
Math, Implementation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Robert Hood
Medium6
Geometry, Sorting+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Substring Set Membership
Medium6
String matching, Trie
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Suspicious Orders
Medium6
Backtracking, Bit manipulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Influence
Medium6
Topological sort, Graph+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Paper Map
Medium6
Brute force, Prefix sum
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Canyon Crossing
Medium6
Union-find, Geometry
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Yahtzee
Medium6
Dynamic programming, Brute force+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Lifeboat Balancing
Medium6
Dynamic programming
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Satellite Photos
Medium6
Geometry, Segment tree+1
No attempts yet
Time limit
2s
Memory limit
256 MB
Judgeable
Fare Dodging
Medium6
Shortest path, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Passwords
Medium6
Combinatorics, Sorting+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Coprime Count in a Range
Medium6
Number theory, Combinatorics
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Wimbledon
Medium6
Probability, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Painting
Medium6
Topological sort, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Another Brick in the Wall
Medium6
Graph, BFS+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Solar Eclipse
Medium6
Geometry, Brute force
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bus Shuttle
Medium6
Brute force, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Genome Evolution
Medium6
Intervals, Array
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Measuring the Median
Medium6
Heap, Sliding window
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Multikill
Medium6
Geometry, Brute force
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Welcome Party
Medium6
Graph, DFS
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Metal
Medium6
Binary search, Greedy+1
No attempts yet
Time limit
5s
Memory limit
256 MB
Judgeable
Set of Rectangles
Medium6
Greedy, Math+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Chomp
Medium6
Game theory, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Klingon Warfare
Medium6
Tree, Hash map+1
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Coloring Book
Medium6
Graph, Combinatorics+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Placing Rooks
Medium6
Graph, DFS
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
String Insert and Print
Medium6
Tree, String+1
No attempts yet
Time limit
10s
Memory limit
256 MB
Judgeable
Circleland
Medium6
Greedy, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
256 MB
Judgeable
Booking Error
Medium6
Shortest path, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Go
Medium6
Simulation, BFS+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Largest Subsequence Number
Medium6
Dynamic programming, String+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Joy of the Cylinder Game
Medium6
Dynamic programming, Sliding window
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Empty Stalls
Medium6
Union-find, Simulation
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Join the Conversation
Medium6
Dynamic programming, Hash map+1
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Kabaleo Lite
Medium6
Greedy, Array+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Last Ant
Medium6
Simulation, Implementation
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Regions Cut by Rectangles
Medium6
Geometry, Graph+1
No attempts yet
Time limit
5s
Memory limit
128 MB
Judgeable
Dragon's Cruller
Medium6
Shortest path, BFS+1
No attempts yet
Time limit
10s
Memory limit
128 MB
Judgeable
Swyper Keyboard
Medium6
Geometry, String matching+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Omar Loves Candies
Medium6
Prefix sum, Greedy+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Mario Kart
Medium6
Dynamic programming, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Stone Game 8
Medium6
Game theory, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Genetically Modified Apple
Medium6
Dynamic programming, String matching
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Tire Groove Cutting
Medium6
Number theory, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
BitTorrent
Medium6
Dynamic programming, Prefix sum
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Bowling Ball
Medium6
Simulation, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
The Exam
Medium6
Math, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Sum of LIS lengths over every consecutive subsequence
Medium6
Dynamic programming, Binary search+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Supercap Travels
Medium6
Math, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Rooks
Medium6
Sorting, Greedy+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Matrix Transformation
Medium6
Math, Greedy
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Breaking the Equations
Medium6
Hash map, Brute force+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Booster
Medium6
Shortest path, Dynamic programming
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Friendship Graph
Medium6
Graph, DFS+2
No attempts yet
Time limit
2s
Memory limit
128 MB
Judgeable
Cartesian Tree
Medium6
Stack, Sorting+1
No attempts yet
Time limit
2s
Memory limit
64 MB
Judgeable
Commuter train
Medium6
Brute force, Sorting
No attempts yet
Time limit
2s
Memory limit
64 MB
Judgeable
Placement of Keys
Medium6
Combinatorics, Math
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Change
Medium6
Greedy, Math
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Singapore Tour
Medium6
Dynamic programming, BFS+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Sequence Prediction
Medium6
Simulation, Math+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Lazycat
Medium6
Dynamic programming, BFS+1
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Street
Medium6
Dynamic programming, Intervals
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Vacation Planning
Medium6
Shortest path, Graph
No attempts yet
Time limit
3s
Memory limit
256 MB
Judgeable
Wormholes
Medium6
Backtracking, Graph+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Building a Ski Course
Medium6
Greedy, Prefix sum+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Genome
Medium6
Graph, Dynamic programming
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Heng crosses the river
Medium6
Shortest path, Graph
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
(ℓ, d) pattern
Medium6
Brute force, String matching
No attempts yet
Time limit
2s
Memory limit
512 MB
Judgeable
Filling a 4 × n Rectangle with Dominoes
Medium6
Dynamic programming, Combinatorics
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Train
Medium6
BFS, Graph+2
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Longest Arithmetic Progression
Medium6
Dynamic programming, Array
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Cube
Medium6
Simulation, BFS+1
No attempts yet
Time limit
2s
Memory limit
1024 MB
Judgeable
Scout Outing
Medium6
Topological sort, Dynamic programming+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Rectangles
Medium6
Sorting, Intervals+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Bowling Score Assistant
Medium6
Backtracking, Simulation+1
No attempts yet
Time limit
3s
Memory limit
128 MB
Judgeable
Get Out 'Da Way!
Medium6
Geometry, Simulation+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Roadblock
Medium6
Shortest path, Graph
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Mirror Field
Medium6
Graph, DFS
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable
Secret Code
Medium6
Dynamic programming, String matching+1
No attempts yet
Time limit
1s
Memory limit
128 MB
Judgeable

Title	Level	Topics	Solved	Time limit	Memory limit	Judge
Sorting by moving pairsDecide whether a permutation of 1 to N can be sorted by repeatedly relocating an adjacent pair as a block.	Medium6	CombinatoricsMath	No attempts yet	1s	128 MB	Judgeable
GameTwo players alternately add to S within a range set by the current parity, and whoever first reaches F loses, so decide if the first player can force a win.	Medium6	Game theoryDynamic programming+1	No attempts yet	1s	128 MB	Judgeable
Sorting the BarbellsHyunwoo sorts N distinct barbells into increasing weight with the smallest possible total of moved weights.	Medium6	GreedyGraph+1	No attempts yet	1s	128 MB	Judgeable
Word LadderFind the shortest word sequence where neighbors share all but one letter after rearranging, endpoints share no letters, and ties break by dictionary order.	Medium6	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
Contest Problem AssignmentSplit up to ten contest problems among three members with individual time limits to solve the largest possible count.	Medium6	Dynamic programmingBit manipulation	No attempts yet	1s	128 MB	Judgeable
CyclingAmong all routes from crossing 1 to crossing n, pick the one with the smallest altitude range and then the shortest length.	Medium6	Shortest pathTwo pointers+1	No attempts yet	1s	128 MB	Judgeable
AlgebraDecide whether a target permutation can be reached from the identity using only rotations of three distinct positions.	Medium6	MathArray	No attempts yet	1s	128 MB	Judgeable
Reverse EngineeringFigure out that the listed program computes the greatest common divisor and output input pairs that produce each requested value.	Medium6	Number theoryMath	No attempts yet	1s	128 MB	Judgeable
Taunt BotSimulate a taunt bot that expands a fixed grammar with round-robin choices to print one taunt per three input words.	Medium6	SimulationString+1	No attempts yet	1s	128 MB	Judgeable
If only I could think Linearly...Given a matrix M and output vector y, find the three nonzero entries of the input vector x with Mx equal to y.	Medium6	MatrixBrute force	No attempts yet	1s	128 MB	Judgeable
Who needs 8 queens when you can have N?Find the lexicographically smallest placement of N non-attacking queens on an N by N board for each test case.	Medium6	BacktrackingRecursion+1	No attempts yet	1s	128 MB	Judgeable
Jill's Tour PathsList every simple route from the start village to the destination within the distance limit, ordered by length then village order.	Medium6	BacktrackingDFS+2	No attempts yet	1s	128 MB	Judgeable
Bounded Cellular AutomataFind every Wolfram rule from 0 to 255 whose bounded run from one black cell first reaches the target row within the step limit.	Medium6	SimulationHash map+1	No attempts yet	1s	128 MB	Judgeable
Unscrambling ImagesThe solver recovers the hidden child order at each quadtree node from the test encoding and restores the secret image.	Medium6	TreeRecursion+1	No attempts yet	1s	128 MB	Judgeable
Prime CavesStarting from cave n on a spiral-numbered grid, descend down-left, down, or down-right to collect the most prime-numbered caves.	Medium6	Dynamic programmingNumber theory+1	No attempts yet	1s	128 MB	Judgeable
BoggleFind all dictionary words on each 4x4 Boggle board with 8-direction steps without reuse, then report the total score, longest word, and word count.	Medium6	TrieDFS+1	No attempts yet	10s	512 MB	Judgeable
Powerbase FormatCount how many integers in each query range lack a powerbase form d1^1+...+dL^L within the length bound using the given digits.	Medium6	BacktrackingDynamic programming+1	No attempts yet	1s	128 MB	Judgeable
Superstitious Helicopter PilotsSimulate the pilot's greedy rule by checking reachability past forbidden points at each step and print the resulting hop sequence in run-length form.	Medium6	Dynamic programmingGreedy	No attempts yet	1s	128 MB	Judgeable
UrnsYou move balls between five urns in proportion to their color shares and print the final counts.	Medium6	SimulationMath+1	No attempts yet	1s	128 MB	Judgeable
Steve JobsoongFind every natural number below 10^8 whose product with the given X moves its first digit to the last position.	Medium6	MathImplementation	No attempts yet	1s	128 MB	Judgeable
Robert HoodGiven C points on a plane, compute the squared distance between the farthest pair of points.	Medium6	GeometrySorting+1	No attempts yet	1s	256 MB	Judgeable
Substring Set MembershipYou receive a set of patterns and query strings and print YES for each query containing a pattern as a contiguous substring, NO otherwise.	Medium6	String matchingTrie	No attempts yet	1s	256 MB	Judgeable
Suspicious OrdersCount the cliques in a network of up to 20 people whose combined ordered items cover at least one of the given attack combinations.	Medium6	BacktrackingBit manipulation+1	No attempts yet	1s	128 MB	Judgeable
InfluenceFrom the candidate set X, pick the person who reaches the most people through transitive influence, breaking ties by smallest id.	Medium6	Topological sortGraph+1	No attempts yet	3s	128 MB	Judgeable
Paper MapTry every horizontal and vertical shift of the fixed sheet grid and print the smallest number of sheets that covers all marked cells.	Medium6	Brute forcePrefix sum	No attempts yet	3s	128 MB	Judgeable
Canyon CrossingDecide whether a path from the left edge to the right edge of a rectangle avoids up to 1000 circular craters.	Medium6	Union-findGeometry	No attempts yet	1s	128 MB	Judgeable
YahtzeeAssign thirteen dice rolls to thirteen Yahtzee categories, including the upper-section bonus, to maximize the total score.	Medium6	Dynamic programmingBrute force+1	No attempts yet	1s	128 MB	Judgeable
Lifeboat BalancingSplit all passengers into two boats with equal head counts (off by one when N is odd) so the two total weights differ as little as possible.	Medium6	Dynamic programming	No attempts yet	1s	128 MB	Judgeable
Satellite PhotosCompute the union area of up to 1000 axis-aligned rectangles in each of up to 100 test cases.	Medium6	GeometrySegment tree+1	No attempts yet	2s	256 MB	Judgeable
Fare DodgingA commuter mixes per-track tickets priced from shortest distances with free rides that risk expected fines to minimize the expected cost from start to end.	Medium6	Shortest pathGraph+1	No attempts yet	1s	128 MB	Judgeable
PasswordsPrint the K-th distinct string formed by concatenating every permutation of N equal-length strings in ASCII order.	Medium6	CombinatoricsSorting+1	No attempts yet	1s	128 MB	Judgeable
Coprime Count in a RangeCount integers in [A, B] whose greatest common divisor with N is 1 for up to 100 test cases.	Medium6	Number theoryCombinatorics	No attempts yet	1s	128 MB	Judgeable
WimbledonCompute the expected match length in minutes from each player's chance of winning a game on serve under best-of-five tennis scoring.	Medium6	ProbabilityDynamic programming	No attempts yet	1s	128 MB	Judgeable
PaintingRecover the lexicographically smallest order in which whole rows or columns were painted to produce each board.	Medium6	Topological sortGraph+1	No attempts yet	1s	128 MB	Judgeable
Another Brick in the WallTry pulling each brick and report the largest total length of bricks that fall once every support below them is gone.	Medium6	GraphBFS+2	No attempts yet	1s	128 MB	Judgeable
Solar EclipsePlace a point as close to the origin as possible while staying at least 2R away from n given disk centers.	Medium6	GeometryBrute force	No attempts yet	1s	128 MB	Judgeable
Bus ShuttleGiven departure tables for both directions and reported meeting times, find the travel times that explain every report.	Medium6	Brute forceMath+1	No attempts yet	1s	128 MB	Judgeable
Genome EvolutionCount the shared gene blocks of length above one that appear as consecutive runs in both chromosomes.	Medium6	IntervalsArray	No attempts yet	1s	128 MB	Judgeable
Measuring the MedianCompute the sum of the medians of every contiguous window of length K over N temperature readings.	Medium6	HeapSliding window	No attempts yet	1s	256 MB	Judgeable
MultikillChoose any blast point on the plane to cover as many given points as possible within radius R and print the best count for each group.	Medium6	GeometryBrute force	No attempts yet	2s	128 MB	Judgeable
Welcome PartySplit interns into the fewest teams where each team shares one first-name or last-name initial.	Medium6	GraphDFS	No attempts yet	1s	128 MB	Judgeable
MetalSort the deposits by x, split them into at most k contiguous groups, and place one horizontal tunnel per group to minimize the largest vertical distance.	Medium6	Binary searchGreedy+1	No attempts yet	5s	256 MB	Judgeable
Set of RectanglesGiven a wire length L, choose the largest set of Pythagorean rectangles with distinct aspect ratios whose total perimeter fits in L.	Medium6	GreedyMath+1	No attempts yet	2s	128 MB	Judgeable
ChompDecide whether each 3-row Chomp position is winning and output a move to a losing position.	Medium6	Game theoryDynamic programming	No attempts yet	1s	128 MB	Judgeable
Klingon WarfarePick one subclan from each ordered clan tree so the pair matches in style, child count and sibling order with the largest size.	Medium6	TreeHash map+1	No attempts yet	5s	128 MB	Judgeable
Coloring BookCount the assignments of K colors to N pictures so each picture i differs from picture f_i unless f_i equals i, modulo 1,000,000,007.	Medium6	GraphCombinatorics+1	No attempts yet	1s	128 MB	Judgeable
Placing RooksPlace as many rooks as possible on an N by N board with pawns so no two share a row or column without a pawn between them.	Medium6	GraphDFS	No attempts yet	1s	128 MB	Judgeable
String Insert and PrintMaintain a single string under positional insertions and print the requested substring for each query.	Medium6	TreeString+1	No attempts yet	10s	256 MB	Judgeable
CirclelandYou start at room R1 on a corridor cycle and visit every room, then leave through any exit while walking the shortest total corridor distance.	Medium6	GreedyPrefix sum+1	No attempts yet	1s	256 MB	Judgeable
Booking ErrorAdd the fewest new segments to the booked ticket so travel from start to destination uses the smallest number of stops the network allows.	Medium6	Shortest pathDynamic programming+1	No attempts yet	1s	128 MB	Judgeable
GoSimulate simplified Go on boards up to 20 by 20, reject the first stone placed on an occupied point, and count each side's stones plus surrounded empty points.	Medium6	SimulationBFS+1	No attempts yet	1s	128 MB	Judgeable
Largest Subsequence NumberPick digits from N in order, without a leading zero, to form the largest value that leaves remainder R when divided by Q.	Medium6	Dynamic programmingString+1	No attempts yet	3s	128 MB	Judgeable
Joy of the Cylinder GameChoose one cell in every row of the cylindrical grid within the step limit so the total is largest, and print the smallest best path.	Medium6	Dynamic programmingSliding window	No attempts yet	1s	128 MB	Judgeable
Empty StallsCows each take the next free stall clockwise from their wish on a ring of N stalls, and the task asks for the smallest stall number left empty.	Medium6	Union-findSimulation	No attempts yet	1s	128 MB	Judgeable
Join the ConversationFind the longest chronological message chain where each message mentions the previous author, breaking ties by smallest indices.	Medium6	Dynamic programmingHash map+1	No attempts yet	2s	128 MB	Judgeable
Kabaleo LitePick a stack for your last chip so your hidden colour stays the strictly most visible colour whatever rivals play, and list every stack with that guarantee.	Medium6	GreedyArray+1	No attempts yet	1s	128 MB	Judgeable
The Last AntSimulate ants walking at speed 1 in a tunnel where meetings at integer points reverse directions and report when the last ant exits and which one it is.	Medium6	SimulationImplementation	No attempts yet	3s	128 MB	Judgeable
Regions Cut by RectanglesCount the regions into which up to 50 axis-aligned rectangle borders divide the plane, including the outer unbounded region.	Medium6	GeometryGraph+1	No attempts yet	5s	128 MB	Judgeable
Dragon's CrullerFind the cheapest sequence of horizontal and vertical slides that turns one 8-tile torus layout into another.	Medium6	Shortest pathBFS+1	No attempts yet	10s	128 MB	Judgeable
Swyper KeyboardExpand a swipe path over a four-row letter grid into every key each segment crosses, then print the first dictionary word that is a subsequence of it.	Medium6	GeometryString matching+1	No attempts yet	1s	128 MB	Judgeable
Omar Loves CandiesFind the largest sum of any non-empty sub-rectangle in a grid whose rows and columns strictly increase.	Medium6	Prefix sumGreedy+1	No attempts yet	3s	128 MB	Judgeable
Mario KartMove between stations when a subset of coins meets the cost limit and matches the distance, and find the fewest moves from the first to the last station.	Medium6	Dynamic programmingGraph+1	No attempts yet	1s	128 MB	Judgeable
Stone Game 8Count pile sizes up to M where the second player wins a take-away game with a fixed move set.	Medium6	Game theoryDynamic programming+1	No attempts yet	1s	128 MB	Judgeable
Genetically Modified AppleInsert priced letters into a DNA string so a given gene appears as a contiguous block at minimum total cost.	Medium6	Dynamic programmingString matching	No attempts yet	1s	128 MB	Judgeable
Tire Groove CuttingCount the distinct horizontal heights that split each of the N+1 strips into its required number of equal pieces.	Medium6	Number theoryMath	No attempts yet	1s	128 MB	Judgeable
BitTorrentChoose the most files whose covering fixed-size pieces fit in the bandwidth budget, where a piece shared by files is paid once.	Medium6	Dynamic programmingPrefix sum	No attempts yet	2s	128 MB	Judgeable
Bowling BallA ball rolls back and forth over valleys and summits while friction drains its energy at each valley, and the task is to find where it finally stops.	Medium6	SimulationMath	No attempts yet	1s	128 MB	Judgeable
The ExamArrange the numbers 1 to n so the smallest gap between neighbors is as large as possible, and print that gap or NIE when it is below k.	Medium6	MathGreedy	No attempts yet	1s	128 MB	Judgeable
Sum of LIS lengths over every consecutive subsequenceSum the LIS lengths of all contiguous subarrays for each test case of distinct integers.	Medium6	Dynamic programmingBinary search+1	No attempts yet	1s	128 MB	Judgeable
Supercap TravelsFor each city distance, compute the best trip fare under the doubling speed profile and output the highest-scoring city per region.	Medium6	MathGreedy+1	No attempts yet	1s	128 MB	Judgeable
RooksMove N rooks with orthogonal steps onto cells with distinct rows and columns using the fewest total moves.	Medium6	SortingGreedy+1	No attempts yet	1s	128 MB	Judgeable
Matrix TransformationDecide whether repeated plus-or-minus-one updates on adjacent cell pairs can turn each matrix into all zeros.	Medium6	MathGreedy	No attempts yet	1s	128 MB	Judgeable
Breaking the EquationsPick twelve values from the given set that satisfy the six addition equations and form the lexicographically smallest tuple.	Medium6	Hash mapBrute force+2	No attempts yet	1s	128 MB	Judgeable
BoosterCompute how many minutes up to K halve-one-edge boosters save on the fastest route from district 1 to district N.	Medium6	Shortest pathDynamic programming	No attempts yet	1s	128 MB	Judgeable
Friendship GraphDecide up to 200000 reachability queries on a directed graph with 2000 vertices, printing 1 when Y is reachable from X.	Medium6	GraphDFS+2	No attempts yet	2s	128 MB	Judgeable
Cartesian TreeBuild the Cartesian tree whose inorder follows one key and heap order follows the other, printing parents and children, or NO when impossible.	Medium6	StackSorting+1	No attempts yet	2s	64 MB	Judgeable
Commuter trainPick the train stopping position inside the platform that maximizes the total nearest-door distance over all passengers, and print twice that maximum.	Medium6	Brute forceSorting	No attempts yet	2s	64 MB	Judgeable
Placement of KeysCount the key placements that open all boxes after forcing open the first two, for each n up to 200.	Medium6	CombinatoricsMath	No attempts yet	1s	128 MB	Judgeable
ChangePay the exact amount from limited 5, 10, 20 and 50 cent coins with the fewest coins, breaking ties toward larger denominations.	Medium6	GreedyMath	No attempts yet	2s	512 MB	Judgeable
Singapore TourStart at C, collect values from up to 14 grid spots with per-step cost 2, and return for the maximum net score.	Medium6	Dynamic programmingBFS+1	No attempts yet	2s	512 MB	Judgeable
Sequence PredictionGiven observed terms and a modulus, predict the next term under the lowest-degree eventually constant, periodic, or polynomial law.	Medium6	SimulationMath+1	No attempts yet	1s	128 MB	Judgeable
LazycatFind the shortest walk on a grid with walls that starts at S, visits every food cell, then ends at the bed.	Medium6	Dynamic programmingBFS+1	No attempts yet	2s	512 MB	Judgeable
StreetChoose up to k non-overlapping blocks of at most t lots to maximize total block length times its minimum height limit.	Medium6	Dynamic programmingIntervals	No attempts yet	2s	512 MB	Judgeable
Vacation PlanningGiven a flight network where every edge touches one of K hubs, count how many of Q trip requests are reachable and sum their cheapest costs.	Medium6	Shortest pathGraph	No attempts yet	3s	256 MB	Judgeable
WormholesCount the pairings of N wormholes into pairs so that walking right and teleporting through pairs can loop forever from some start.	Medium6	BacktrackingGraph+1	No attempts yet	1s	128 MB	Judgeable
Building a Ski CourseFind the largest square stamp size that can repaint the given rough and smooth grid when later stamps cover earlier ones.	Medium6	GreedyPrefix sum+1	No attempts yet	1s	128 MB	Judgeable
GenomeFind the length of the longest sequence that appears as a subsequence in every given permutation.	Medium6	GraphDynamic programming	No attempts yet	2s	512 MB	Judgeable
Heng crosses the riverFind the fewest 90-degree board rotations needed to walk from the left bank to the right bank across an N by N island grid.	Medium6	Shortest pathGraph	No attempts yet	2s	512 MB	Judgeable
(ℓ, d) patternFind the unique length-l lowercase string within Hamming distance d of some substring in every given string.	Medium6	Brute forceString matching	No attempts yet	2s	512 MB	Judgeable
Filling a 4 × n Rectangle with DominoesCount the tilings of a 4 by n board with dominoes and print the count modulo 1000 without leading zeros.	Medium6	Dynamic programmingCombinatorics	No attempts yet	1s	128 MB	Judgeable
TrainFind the fewest group moves that shift the wanted car order from track one to track two using the middle track.	Medium6	BFSGraph+2	No attempts yet	1s	128 MB	Judgeable
Longest Arithmetic ProgressionFind the length of the longest subsequence of the given sorted list that forms an arithmetic progression.	Medium6	Dynamic programmingArray	No attempts yet	2s	1024 MB	Judgeable
CubeDecide whether six numbered cells in a 6 by 6 grid fold into a cube and report the face opposite face 1.	Medium6	SimulationBFS+1	No attempts yet	2s	1024 MB	Judgeable
Scout OutingScouts split along every DAG trail and regroup at each station; report the last arrival time, the total waiting spread, and the stations with departure slack.	Medium6	Topological sortDynamic programming+1	No attempts yet	1s	128 MB	Judgeable
RectanglesCompute the total area covered by up to 1000 axis-aligned rectangles, counting overlaps once.	Medium6	SortingIntervals+1	No attempts yet	1s	128 MB	Judgeable
Bowling Score AssistantGiven eight frames of bowling scores and the rival total, find the lexicographically smallest rolls in frames 9 and 10 that win, or report impossible.	Medium6	BacktrackingSimulation+1	No attempts yet	3s	128 MB	Judgeable
Get Out 'Da Way!Simulate up to ten bullets fired at a moving flat target and mark each hit block with an asterisk.	Medium6	GeometrySimulation+1	No attempts yet	1s	128 MB	Judgeable
RoadblockFind how much the shortest path from field 1 to field N grows when an adversary doubles the length of exactly one edge.	Medium6	Shortest pathGraph	No attempts yet	1s	128 MB	Judgeable
Mirror FieldCount the most reflections a border beam makes bouncing through a grid of diagonal mirrors, or report -1 if it loops forever.	Medium6	GraphDFS	No attempts yet	1s	128 MB	Judgeable
Secret CodeCount the sequences of operations that build the given string from a source of length at least 2 by gluing each string to a copy missing one end character.	Medium6	Dynamic programmingString matching+1	No attempts yet	1s	128 MB	Judgeable